I wonder if they cut it out of concern that making all three major (non-Mace Windu) black characters in the series related was… questionable.
Maybe, but they failed to realize how much more sense it makes for Jannah to be Finn’s sister than for her to be Lando’s daughter. Seriously, what does the latter contribute to the story? We should cut the relation to Lando and make her Finn’s sister, not have both.